'Brexit' Referendum: Polls Close in U.K. Vote on Future in EU

A man shelters from the rain as he arrives at a polling station in London on June 23, 2016, as Britain holds a referendum on whether to stay in, or leave the European Union (EU).NIKLAS HALLE'N / AFP - Getty Images

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LONDON — Europe held its breath early Friday after Britons voted in a national referendum on whether or not to quit the European Union, with the outcome on a knife-edge after a bitterly divisive campaign.

The polls closed at 10 p.m. Thursday local time (5 p.m. ET). A record-setting 46.5 million people in the U.K. registered to cast their ballot over what has been dubbed the "Brexit" question — with 71 percent turning out to vote.

With around 17.5 million ballots counted, "Leave" was at 51.3 percent and "Remain" at 48.7 percent. However, 161 of the U.K.'s 382 local centers had yet to report and millions of votes remained uncounted.

Supporters of the "Stronger In" Campaign react as results of the EU referendum are announced in London early Friday.ROB STOTHARD / AFP - Getty Images

Opinion polls before the historic vote suggested the "Leave" campaign was virtually tied with those urging voters to "Remain" in the 28-country trading bloc.

U.K. Independence Party leader Nigel Farage, a key figure in the "Leave" campaign, was upbeat early Friday. He tweeted: "I now dare to dream that the dawn is coming up on an independent United Kingdom."

In an subsequent press conference, Farage added: "If the predictions now are right, this will be a victory for real people ... Let June 23 go down in our history as our independence day."

Financial markets were keenly awaiting an outcome after months of uncertainty.

Mary Brookes, 51, a teacher and local resident wearing a "Remain" button, said: “I hope people will see sense and keep us in the EU. It is far too important to throw away because of temporary problems.”

Others were just happy that the campaign was finally coming to an end.

“I feel better now it is over,” said Jojo Lands, a nurse aged in her 40s. “It is on television, Facebook, everywhere. I don’t want to talk about it again.”

The final week of campaigning included a bruising televised debate and a personal appeal by Prime Minister David Cameron from the steps of 10 Downing Street — and was overshadowed by last week's murder of pro-EU lawmaker Jo Cox.

Ballot papers will be counted at 382 local centers across Britain and Northern Ireland, with the results relayed to 12 regional centers that will also declare the totals for each side.

The first of the local results started coming in shortly after midnight early Friday (around 7 p.m. Thursday ET) and the final result — not expected until later Friday — will be declared by the chief counting officer in Manchester, northern England.

Analysts were divided about what a high or low turnout would mean for either side. John Curtice, a polling expert and professor of politics at the University of Strathclyde, believes a low turnout would benefit the "Leave" side because "Remain" voters are less motivated.

However, Justin Fisher, professor of politics at Brunel University, told Bloomberg that supporters of Brexit were generally less politically-engaged and less likely to vote. "If 'Leave' manage to mobilize them, then a high turnout may not be good for 'Remain,'" he said.

Alastair Jamieson

Alastair Jamieson is a London-based reporter, editor and homepage producer for NBC News.

Phil Helsel

Phil Helsel is a reporter for NBC News.

Jason Cumming

Jason Cumming is London editorial manager and a senior news editor for NBC News Digital.